1. Technical Field
Embodiments of the present disclosure relate to semiconductor integrated circuits and, more particularly, to internal voltage generation circuits.
2. Related Art
In general, semiconductor devices receive a power supply voltage signal VDD and a ground voltage signal VSS from an external system to generate internal voltage signals used in operations of internal circuits constituting each of the semiconductor devices. The internal voltage signals for operating the internal circuits of the semiconductor devices may include a core voltage signal VCORE supplied to a memory core region, a high voltage signal VPP (also, referred to as a boost voltage signal) used to drive or overdrive word lines, and a low voltage signal VBB (also, referred to as a back-bias voltage signal) applied to a bulk region (or a substrate) of NMOS transistors in the memory core region.
The core voltage signal VCORE may have a positive voltage which is lower than the power supply voltage signal VDD supplied from the external system. Thus, the core voltage signal VCORE may be obtained by lowering a level of the power supply voltage signal VDD to a certain level. In contrast, the high voltage signal VPP may have a level which is higher than a level of the power supply voltage signal VDD, and the low voltage signal VBB may have a negative voltage which is lower than the ground voltage signal VSS. Thus, charge pump circuits may be required to generate the high voltage signal VPP and the low voltage signal VBB.